var obj={
    name:'lerry',
    age:18
};
Object.defineProperty(obj,'name',{
    configurable:false,
    writable:true,
    enumerable:true,
    value:'zahngsan'
})
delete obj.name;
for(let key in obj){
    console.log(key,obj[key],'可枚举属性');
}
console.log(obj);